放射物理学课件：Breast Cancer

1、 Breast CancerEpidemiology and risk factorsDignosisPrognstic factorsTreatmentsEpidemiology and risk factorsEpidemiologyThe most common invasive cancer in women.Comprises 22.9% of invasive cancers in women, 16% of all female cancers.The number of cases worldwide has significantly increased since the

2、1970s. Epidemiology The incidence of breast cancer varies greatly around the world. 2015Epidemiology In China, the economic developed cities have higher morbidity of breast cancer.Incidence 2009 in china Epidemiology Breast cancer also occurs in males. Incidences approximately 100 times less. Same s

3、tatistical survival rates as women.Risk factorsGenderbeing a womanThe lifetime risk in men and in women 0.11% vs 13% Risk factorsAge:the chance of getting breast cancer increases with age.Estimated risk of developing breast cancer by age, females, UK, 2008 Risk factorsIn China, highest risk age grou

4、p: 45-55ys, younger than that in developed countries (55-79 ys)Risk factorsFamily history Genetics Carriers of alterations in either of two familial breast cancer genes BRCA1 or BRCA2 up to an 80% risk of being diagnosed with breast cancerRisk factorsBreast diseaseAtpyical HyperplasiaIntraductal car

5、cinoma in situIntralobular carcinoma in situA previous diagnosis of breast cancer Radiation exposure The effect is strongly related to age at exposureRisk factorsEndogenous and exogenous hormones- Early age at menarche- Late menopause- Nulliparity- First birth after the age of 35 - Oral Contraceptiv

6、es (OCs)- Hormonal replacement therapy (HRT) - Breastfeeding: reduce riskRisk factorsLifestyle factors - high body mass index (BMI), moderately increases the risk of post-menopausal breast cancer - physical activity （reduce risk） - alcoholRace a slightly higher risk in Caucasian women than in Africa

7、n-American, Asian, Hispanic, and Native American women. PATHOLOGYPathologyThe 2012 World Health Organization (WHO) classification of tumors of the breast recommends the following pathological types: PathologyNoninvasive lesions Lobular neoplasia Lobular carcinoma in situ Intraductal proliferative le

8、sions Usual ductal hyperplasia Ductal carcinoma in situ Intraductal papillary neoplasmsPapilloma Intraductal papillary carcinoma Nipple adenoma Pagets disease of the nipple Microinvasive carcinoma PathologyInvasive breast carcinomas Invasive carcinoma of no special type (invasive ductal carcinoma )

9、Invasive lobular carcinoma Tubular carcinoma Medullary carcinoma Mucinous carcinoma Adenoid cystic carcinoma Neuroendocrine tumours Metaplastic carcinomas Invasive papillary carcinoma Lipid-rich carcinoma Secretory carcinoma Apocrine carcinoma Inflammatory carcinomaDiagnosisSigns and SymptomsMost co

10、mmon: lump or thickening in breast. Often painlessChange in color or appearance of areolaRedness or pitting of skin over the breast, like the skin of an orangeDischarge or bleedingChange in size or contours of breastDiagnosisMetastasis lymphatic Lymph Node Areas Adjacent to Breast AreaA Pectoralis m

11、ajor muscleB Axillary lymph nodes: levels IC Axillary lymph nodes: levels IID Axillary lymph nodes: levels IIIE Supraclavicular lymph nodesF Internal mammary lymph nodesDiagnosisDistance metastasis ：bones，lung，brain，liver, soft tissue and adrenal glands，etcs。Diagnosis Clinical examination including

12、inspection and palpation specificity :90% but there also many cancers may go unnoticed so it becomes useful to complement other texts.DiagnosisMammographyprocess of using low-dose amplitude-X-rays to examine the breast. used as a diagnostic and a screening tool. goal : early detection and diagnosis

13、of breast cancer. DiagnosisMammography EquipmentDiagnosis Two of the most important mammographic indicators of breat cancersMasses Malignant masses have a more spiculated appearanceDiagnosisMicrocalcifications: Tiny flecks of calcium like grains of salt in the soft tissue of the breast.DiagnosisMRIS

14、ensitivity from 88 to 100%. Especially useful for distinguishing recurrence in a previously irradiated breast from scar tissue. Detect any additional lesions that might change the surgical approach DiagnosisUltrasonography The main use is to distinguish between a solid mass and cyst. Useful for dens

15、ity breast. More false-positive results. Imaging tests are sometimes used to detect metastasis : chest X-ray, bone scan, CT scan, MRI, and PET-CT scanning. DiagnosisBiopsy -Fine-needle aspiration cytology (FNAS) The sensitivity in diagnosing malignancy has been reported to be 90% to 95%, with almost

16、 no false-positive results. -Ultrasound or stereotactic core biopsy. -Mammotome -Excisional biopsy StagingTNM System (2010)T: tumor Tx means that the tumor size cannot be assessed T0: No available of primary tumors Tis: Carcinoma in situ Tis（DCIS）: ductal carcinoma in situ Tis（LCIS）: lobular carcino

17、ma in situ Tis（Paget）: Pagets disease of the nipple NOT associated with invasive carcinoma and/or carcinoma in situ (DCIS and/or LCIS) in the underlying breast parenchyma. StagingT1 Tumor 20 mm in greatest dimension T1mic Tumor 1 mm in greatest dimension T1a Tumor 1 mm but 5 mm in greatest dimension

18、. T1b Tumor 5 mm but 10 mm in greatest dimension T1c Tumor 10 mm but 20 mm in greatest dimension StagingT2 Tumor 20 mm but 50 mm in greatest dimension T3 Tumor 50 mm in greatest dimension StagingT4 Tumor of any size with direct extension to the chest wall and/or to the skin (ulceration or skin nodul

19、es) T4a Extension to the chest wall, not including only pectoralis muscle adherence/invasion StagingT4b Ulceration and/or ipsilateral satellite nodules and/or edema (including peau dorange) of the skin, which do not meet the criteria for inflammatory carcinoma T4c Both T4a and T4b T4d Inflammatory c

20、arcinomaStagingN: regional lymph nodes Clinical Nx Regional lymph nodes cannot be assessed (e.g., previously removed). N0 No regional lymph node metastases. N1 Metastases to movable ipsilateral level I, II axillary lymph node(s). StagingN2 Metastases in ipsilateral level I, II axillary lymph nodes t

21、hat are clinically fixed or matted; or in clinically detected ipsilateral internal mammary nodes in the absence of clinically evident axillary lymph node metastases. StagingN3 Metastases in ipsilateral infraclavicular (level III axillary) lymph node(s) with or without level I, II axillary lymph node

22、 involvement; or in clinically detected ipsilateral internal mammary lymph node(s) with clinically evident level I, II axillary lymph node metastases; or metastases in ipsilateral supraclavicular lymph node(s) with or without axillary or internal mammary lymph node involvement. StagingPathologic (PN

23、) pNx Regional lymph nodes cannot be assessed (for example, previously removed, or not removed for pathologic study) pN0 No regional lymph node metastasis identified histologically StagingpN1 Micrometastases; or metastases in 13 axillary lymph nodes; and/or in internal mammary nodes with metastases

24、detected by sentinel lymph node biopsy but not clinically detectedStagingpN2 Metastases in 49 axillary lymph nodes; or in clinically detected internal mammary lymph nodes in the absence of axillary lymph node metastases StagingpN3 Metastases in 10 or more axillary lymph nodes; or in infraclavicular

25、(level III axillary) lymph nodes; or in clinically detected ipsilateral internal mammary lymph nodes in the presence of one or more positive level I, II axillary lymph nodes; or in more than three axillary lymph nodes and in internal mammary lymph nodes with micrometastases or macrometastases detect

26、ed by sentinel lymph node biopsy but not clinically detected; or in ipsilateral supraclavicular lymph nodes.StagingMM0 No clinical or radiographic evidence of distant metastases.M1 Distant detectable metastases as determined by classic clinical and radiographic means and/or histologically proven 0.2

27、 mm. AJCC Stage (7th edition)STAGETNMSTAGE 0TisN0 M0 STAGE IAT1N0M0STAGE IB T0-1N1miM0STAGE II AT0-1T2N1N0M0M0STAGE II B T2T3N1N0M0M0STAGE III A T0-2T3N2N1-2M0M0STAGE III B T4N0-2M0STAGE III C Any T N3M0STAGE IV Any T Any NM1Prognosis Factors PROGNOSIS FACTORSAge ：women younger than 40 years have a

28、poorer prognosis than post-menopausal women. The stage : has a greater effect on the prognosis than the other considerations. The higher the stage at diagnosis, the poorer the prognosis. Breast cancer grade: The Nottingham modification of the Scarff-Bloom-Richardson grading system grades breast carc

29、inomas by adding up scores for tubule formation nuclear pleomorphism mitotic count each of which is given 1 to 3 points. 3-5: Grade 1 tumor (well-differentiated). 21% Best prognosis6-7: Grade 2 tumor (moderately differentiated). 50% Medium prognosis.8-9 Grade 3 tumor (poorly differentiated). 29% Wor

30、st prognosis.The presence of estrogen and progesterone receptors (ER and PR) in the cancer cell is important in guiding treatment. The HER2/neu(ERBB2) oncogene amplified and/or overexpressed in approximately 20% of breast cancers, a strong prognostic factor for relapse and poor overall survival, par

31、ticularly in node-positive patients.TREATMENTSSURGERYMASTECOMY: complete surgical resection of the breast tissue. Types of mastectomy include radical mastectomymodified radical mastectomysimple mastectomyskin-sparing mastectomynipple-areolar sparing mastectomy. Breast-conserving surgery （BCS）is an o

32、peration to remove the cancer and some normal tissue around it. lumpectomy, partial mastectomy, segmental mastectomy, quadrantectomy, or breast-sparing surgery. Contraindicationsto BCS. Multicentric disease in separate quadrants of the breast.Diffuse malignant microcalcifications on mammography.A hi

33、story of prior therapeutic RT. Pregnancy in the first two trimester.Persistently positive resection margins after multiple attempts at reexcision .SURGERYRADIOTHERAPYRADOITHERAPYPostmastectomy radiation therapy (PMRT)Radiotherapy Postmastectomy radiation therapy (PMRT) PMRT has two potential benefit

34、s: decrease about 20% of local-regional recurrence. increase in long-term breast cancer-specific and overall survivals(3%-5% of 15-20 years OS).Whole breast radiation therapy (WBRT) after BCS The results of meta-analysis showed that WBRT resulted in:A nearly 50% reduction in the 10-year risk of any

35、first recurrence compared with BCS alone (19% vs 35% ). A reduction in the 15-year risk of breast cancer death (21% vs 25%). WBRT is recommended for patients after BCS.TECHNIQUEThe patient is immobilized supine to ensure movements are minimized. Radiopaque catheters are applied to the patient to del

36、ineate the borders of the treatment fields, any scars, and match line junctions. Large breasts the planned position can be done lateral or prone. Tangential fields: for breast or chest wall Superior: suprasternal notch Inferior: 1-2 cm inferior of the inframammary fold Medial: anatomical midline Lat

37、eral: midaxillary line Anterior: about 1cm anterior of breast, to ensure coverage during normal breathing Posterior: to cover chest wall, with a maximum lung depth of 2cmSupraclavicular field matched to the tangential fields of the breast to prevent any overdose to the junction of the fields. Shield

38、ing is used to shield the shoulder joint and the apex of the lung. angle this field 10 degrees laterally so that divergence does not enter the cervical spine. BordersMedial: 1cm ipsilateral to anatomical midline (to avoid the oesophagus)Inferior: to match breast tangentialsSuperior: to cover the thy

39、roid cartilage, Lateral：extends to the coracoid process（only include the supraclavicular and infraclavicular nodes） extends to the mid humeral head （include the full axilla）Posterior axillary boost (PAB) If coverage of deep nodes lymph node levels is desired or dose coverage for supraclavicular fiel

40、d provides inadequate coverage due to axillary node seperation, then a PAB may be prescribed to provide optimal dose distribution.BordersMedial: 1.5-2.0 cm of lungLateral: Lateral posterior axillary foldInferior: to match breast tangential fieldsSuperior: splits claviclePrescriptionAnterior SCV fiel

41、d and the posterior PAB field overlap varies from patient to patient. Dose is prescribed such that the combined dose distribution is optimal and provides coverage of nodal volumes. IMNsseparates from tangential fields： Medial: anatomical midline Lateral: 5cm to midline Superior to inferior: the firs

42、t three interspaces.Combination of electron and photon beams IMNs within tangential fields： 3DCRT and IMRTPatient immobilization Imaging CT scan of the treatment area is obtained while patient remains in the treatment position, to allow for precise target delineation. Delineation of the target volum

43、es：clinicians use the imaging studies to contour the target volumes, as well as normal tissues(heart, lung, etcs.) Dose and schedule definition the dose for target volumes and normal tissues : CTV，PTV lung (V205cmClear margin 1mmFields of irradiation includes: the chest wall (node negative) + the regional nodes (supraclavicular and infraclavicular nodes). IMNs(internal mammary nodes) RT is controversial.Axilla fossa RT is for patients wi